This invention relates to an apparatus for producing particulate material from compact masses of material. More particularly the present invention is concerned with an apparatus for producing particulate material from compressed or compacted masses of material such as insulation materials and then pneumatically blowing or spraying such materials. This invention further relates to an improved feeder assembly for such an apparatus which pneumatically blows such materials to the desired location.
In general the types of insulation materials with which the present invention is concerned include loose insulating material that is generally, but not exclusively, fibrous such as granulated rock wool, granulated mineral fiber wool, glass fiber materials, cellulose fibers, expanded mica, etc. This insulation material may be in particulate form and may be either blown dry or sprayed through a nozzle with liquid added to form an insulating and sealing coating on any surface. The insulation material has been blown on conven-tional ceilings of places of habitation or working areas as well as in mine shafts, tunnels and the like.
The insulating material used in conventional insulation spraying and blowing machines is in a relatively loose condition but it is usually packed under high compression in bags or sacks for shipment to the user. Upon being opened these bags or sacks usually yield compressed masses of the insulation material that render the insulation material difficult to use in conventional apparatus that require feeding through an air hose to the area to be insulated. Because of the very low density of the material there is usually formed under the compaction in the bags or sacks large masses that are perhaps up to a foot or more in diameter and cannot be easily separated into the individual particulate material. Even smaller masses in the form of nodules that may be up to several inches in diameter are unsuitably large to be fed through an air hose or to be effective in providing the desired insulation. These large masses as well as the nodules must be separated into particulate materials, although they may be to some extent intertwined with each other and not be discrete. The fibrous material forming the majority of the insulating materials is typically the most difficult to handle unless it is kept in a semi-fluidized state which desirably relies upon the material being particulate. The term "particulate" includes not only particles but also one or more intertwined or overlapping fibers and for convenience the term "particulate material" will therefore include materials formed as particles as well as such fibers.
The parent application over which this invention is an improvement discloses an apparatus for producing preselected and consistent density of particulate material from compact masses of insulation materials and then pneumatically dispensing the material in a uniform flow. The apparatus includes a hopper for receiving the compact masses, an outlet positioned in the bottom of the hopper and a shredding zone located within the upper portion of the hopper for shredding large compact masses into smaller masses or nodules. A shredding means including a plurality of counterrotating shafts and having a plurality of radially extending bars extend through the hopper and have orbits that mutually overlap. An auger is positioned below the shredding means and above the outlet for moving the material along the hopper. Below the auger is a tearing and separating zone that receives the material from the outlet and operates to tear and separate any of the nodules of the material into particulate material. The tearing and separating zone includes means having a plurality of counterrotating brush elements through which the material passes to be torn and separated. The particulate material is then received and dispensed by a pneumatic trans-port means, which includes a rotating air lock having an inlet at one end and an end plate at the other or exhaust end of the air lock. An exhaust metering port is formed in the end plate with a graduated opening enlarged towards the direction of rotation of the air lock to permit the particulate material to be progressively discharged.
The particulate matter was not, however, being completely discharged in the above-described apparatus. In particular, the material was getting stuck in the narrow part of the discharge airlock and around the bolts holding the sealing strips to the long support members. Also, insufficient pressure was being developed in the airlock cells to blow or spray the materials resulting in inconsistent and incomplete filling and dumping of the airlock chambers.
It was also found that to replace the rubber seals as they wore out required that the rotor be removed from the feeder barrel. This meant that more skilled repair personnel were needed and that the machine would be out of use for longer periods of time.